This invention relates to a truck for picking up, depositing and transporting containers which are adapted to be coupled to said truck, preferably a garbage-collecting truck provided with replaceable containers, which truck comprises a pivoted frame, which is pivotally movable by a hydraulic-cylinder unit about a transverse axis disposed in the rear portion of the chassis, also comprises a carriage, which is movably mounted on said pivoted frame and reciprocable by a hydraulic piston-cylinder unit and adapted to be coupled to the container by a hook and adapted to displace the container on the pivoted frame.
A known truck of that kind is known from the prior German Patent Application P 38 40 246.7, which is no prior publication. Said known truck permits containers provided on said truck to be deposited without a need for additional lifting tackle and in such a manner that the containers stand upright on their rear side surface and the truck is also adapted to pick up containers which have been deposited in that manner and to effect said picking up without a need for additional transporting and lifting means.
There is also a desire to transfer containers from a loading surface of a truck to a trailer so that the containers can be transported in larger sets to their destinations and to transfer containers from trailers to the loading surface of a truck.
For this reason it is an object of the present invention to provide a truck which is of the kind described first hereinbefore and can be used to deposit transport containers on trailers and to pick up the transport containers from such trailers and to accomplish this without a need for additional transporting means and/or lifting tackle.
In a truck of the kind described first hereinbefore that object is accomplished in accordance with the invention in that means are provided for transferring a container to a trailer that is coupled to the truck and for transferring a container from the trailer to the truck and said means have the following features:
a) The trailer is provided with a trailer carriage, which is movable on the trailer in the longitudinal direction by drive means, and the rear end of the container is adapted to be locked to said carriage when said rear end has been pushed onto said carriage;
b) the pivoted frame is provided with drive means and gearing for pivotally moving said pivoted frame through about 180 degrees.
By means of the truck, a container which is coupled to the pivoted frame of the truck can be deposited on a trailer which is coupled to the truck and said depositing can be accomplished in that the pivoted frame initially rests in a horizontal position on the chassis and the container is displaced rearwardly by means of the carriage to such an extent that the rear end of the container is pushed onto the trailer carriage and is coupled thereto. Thereafter the pivoted frame is erected in known manner through about 90 degrees while the hydraulic piston-cylinder unit for moving the carriage is controlled to be in a floating mode so that relative movements between the carriage and the pivoted frame can be performed without giving rise to constraints and/or without a need for complicated control means. When the pivoted frame has reached an approximately vertical position, the trailer carriage is displaced to pull the rear end of the container as far as to the rear end of the trailer while the drive means for the pivoted frame are controlled to be in a floating mode so that hydraulic drives cannot oppose each other and a gentle deposition of the container on the trailer is ensured. During the last phase of the pivotal movement of the pivoted frame through an angle of 180 degrees the drive means for the pivoted frame, which are in a floating mode, may suitably be throttled so that a hard impact of the container on the trailer will be prevented.
When the container has been deposited on the trailer the pivoted fame is uncoupled from the container in that the carriage retracts the hook out of the eye of the container.
The operation by which a container is picked up from a trailer which is coupled to the truck is performed correspondingly by a reverse operation. At first, the hook provided on the carriage is coupled to the eye of the container and the pivoted frame which has been turned out through 180 degrees is then erected to a vertical position. At that time the drive means for the trailer carriage are controlled to be in a floating mode in order to permit a simple control without a constraint. When the pivoted frame of the truck is vertical that frame is lowered to a horizontal position on the base frame of the chassis, as has basically been described in prior German Patent Application P 38 40 346.7.
The turning of the pivoted frame through 180 degrees from a horizontal position on the base frame of the chassis of the truck may be imparted to the pivoted frame by conventional hydraulic drive means and gearing. Suitable drives include swivel drives, crank drives and gear drives. In accordance with a preferred feature the pivoted frame is adapted to be erected to an approximately vertical position by means of a pivoted lever, which is provided on the pivoted frame and is engaged with a stop provided on the pivoted frame and to which one end of the hydraulic piston-cylinder unit is pivoted. The other end of said unit is pivoted to the chassis, another hydraulic piston-cylinder unit is connected at one end to the pivoted frame and at the other end to the lever in such manner that said other hydraulic piston-cylinder unit imparts to the lever a pivotal movement relative to the pivoted frame so that the pivoted frame, the chassis, the first hydraulic piston-cylinder unit and the lever constitute a four-bar linkage and the pivoted frame is adapted to be turned from its approximately vertical position to a position resulting from a movement through about 180 degrees.
The hook for receiving the eye of the container is suitably pivoted to the carriage and adapted to be locked. The locked position is required, inter alia, to permit a picking up and depositing of a container which stands on its rear side face. A hook which is locked to the carriage is also required for a displacement of the container in its horizontal position on the pivoted frame to a position over the carriage.
In a further embodiment of the invention that part which carries or constitutes the hook consists of a two-armed lever, the other arm of which constitutes a gravity pendulum, which holds the unlocked hook in a vertical position. By that design it will be ensured that when the pivoted frame lies horizontally on the chassis the hook will assume an exactly defined, vertical position in which it can be locked, e.g., by a hydraulically actuated pin, to a carriage which carries said pin so that the pivoted frame can properly perform the required functions as containers are deposited and picked up.
In a second embodiment the object underlying the invention is accomplished in a truck in that means are provided for transferring a container to a trailer, which is coupled to the truck, or the like and for a transfer of a container from the trailer or the like onto the truck, with the following features:
a) The trailer or the like is provided with a carriage, which is movable on the trailer in the longitudinal direction by drive means and the rear end of the container which has been pushed onto said carriage is adapted to be locked thereto;
b) when the carriage has been displaced by a retraction of the piston rod the cylinder of the pressure fluid-operable piston-cylinder unit for displacing the carriage on the pivoted frame is adapted to be shifted to a second pivoted holder so that after the piston rod has been extended the container is displaced further in a substantially horizontal position onto the trailer or the like.
In accordance with the first teaching that end of the container which is locked to the carriage must be lifted by a pivotal movement of the pivoted frame through 180 degrees. The second teaching in accordance with the invention permits the container to be pushed in a substantially horizontal direction onto a trailer, transport truck or rail car. But where the second teaching in accordance with the invention is followed it may be necessary to lift the pivoted frame to such an extent that the fluid-operable piston-cylinder unit with its piston rod in a retracted position can be pivotally moved from its first locked position to its second locked position without an obstruction.
If the second teaching in accordance is followed, the required large transfer displacement will be effected by only one pull-push cylinder in that the cylinder is shifted between two different positions and in said positions is pivotally locked to the pivoted frame. In that case the ports provided for the hydraulic liquid on the fluid-operable piston-cylinder unit must be so arranged and controlled that the cylinder is adapted to perform the pivotal movement through about 180 degrees which is required for its shifting.
In a truck of the kind used in accordance with the invention the second teaching in accordance with the invention may be adopted alone or in addition to the first teaching stated.
The hook for locking the container to the carriage is suitably pivoted to the carriage on a horizontal axis and is adapted to the locked to the carriage by automatically operable locking means. Such locking means may consist of a locking pin, which is adapted to be displaced by a fluid-operable piston-cylinder unit.
In accordance with a further feature of the invention the piston rod is provided at its free end with a cross-piece, which at its center is pivoted to the carriage and at the ends of which the ends of piston rods are movably mounted like cranks whereas the associated cylinders are movably mounted on the carriage on both sides of the cross-piece. The cylinders serve as retaining and damping cylinders for the displacing cylinder so that the latter cannot strike down freely when it has been released from its first swivel mount. Because the piston rods are pivoted like cranks, the displacing cylinder can automatically be pivotally moved from one swivel mount to the other and vise versa.
The hook is suitably double-armed and the piston rod of the fluid-operable piston-cylinder unit for displacing the carriage is pivoted to the lower arm, which is not provided with the hook.